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    <a href="../index.html">cppreference.com</a> &gt; <a href=
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    "namespace.html">namespace</a>
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  <div class="name-format">
    namespace
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    Syntax:
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  <pre class="syntax-box">
  namespace name {
  declaration-list;
  }
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  <p>The namespace keyword allows you to create a new scope. The name
  is optional, and can be omitted to create an unnamed namespace. Once
  you create a namespace, you&#39;ll have to refer to it explicitly or
  use the <a href="using.html">using</a> keyword.</p>

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    Example code:
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    <pre class="example-code">
   namespace CartoonNameSpace {
     int HomersAge;
     void incrementHomersAge() {
       HomersAge++;
     }
   }
   int main() {
     ...
     CartoonNameSpace::HomersAge = 39;
     CartoonNameSpace::incrementHomersAge();
     cout &lt;&lt; CartoonNameSpace::HomersAge &lt;&lt; endl;
     ...
   }            
</pre>
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    Related topics:
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    <a href="using.html">using</a>
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